109 research outputs found
A Fresh Look at the Type III Secretion System: Two-Step Model of Effector Translocation in Pathogenic Bacteria
The SseC translocon component in Salmonella enterica serovar Typhimurium is chaperoned by SscA
Background: Salmonella enterica is a causative agent of foodborne gastroenteritis and the systemic disease known as typhoid fever. This bacterium uses two type three secretion systems (T3SSs) to translocate protein effectors into host cells to manipulate cellular function. Salmonella pathogenicity island (SPI)-2 encodes a T3SS required for intracellular survival of the pathogen. Genes in SPI-2 include apparatus components, secreted effectors and chaperones that bind to secreted cargo to coordinate their release from the bacterial cell. Although the effector repertoire secreted by the SPI-2 T3SS is large, only three virulence-associated chaperones have been characterized. Results: Here we report that SscA is the chaperone for the SseC translocon component. We show that SscA and SseC interact in bacterial cells and that deletion of sscA results in a loss of SseC secretion, which compromises intracellular replication and leads to a loss of competitive fitness in mice. Conclusions: This work completes the characterization of the chaperone complement within SPI-2 and identifies SscA as the chaperone for the SseC translocon
Incidence of particle size distribution in peanut husks bonded panels
El propósito de esta etapa de la investigación fue conocer la influencia de la variación del tamaño y de la forma de partículas cáscaras de maní en las propiedades de paneles aglomerados encolados con resina ureica. Se formularon paneles con cáscaras molidas (densidad de las partículas: de 81 Kg/m3), paneles con cáscaras enteras (densidad de las partículas: 200 Kg/m3) y dos combinaciones de las mismas. Los resultados alcanzados demostraron que los paneles compuestos por partículas de cáscaras de maní molidas (finas) mejoraron las propiedades físicas y mecánicas respecto de las placas que incorporaron partículas de mayor tamaño. Los valores de densidad en paneles con partículas molidas fueron 628,67 Kg/m3; absorción de agua 65,3% y 79,75% a 2 h y 24 h respectivamente; e hinchamiento de 9,9% y 14,35% medidos a 2 h y 24 h respectivamente. En relación a la caracterización de propiedades mecánicas de flexión, los valores registrados en muestras elaboradas con partículas finas de cáscaras de maní resultaron en MOR: 3,58 MPa, LOP 2,26 MPa y MOE 627 MPa. Con respecto a tenacidad, el mayor valor fue observado en los tableros elaborados con partículas enteras de cáscaras de maní: 1,58 MPa. Las propiedades caracterizadas se encuentran aun por debajo de las propiedades de las placas comerciales de madera de tipo MDF y aglomerados convencionales. Ajustes al proceso de elaboración de las placas de cáscaras de maní serán incorporados en futuros trabajosThe purpose of this stage was to determine the influence of particle size and shape of peanut husks on the properties of panels made with urea resin. Panels were made with milled husks200 Kg/m3 ) and unmilled husks (81 Kg/m3 ) and two combinations thereof. The results showed that the panels made with milled husks improved physical and mechanical properties with respect to the panels that incorporated unmilled particles. The density values in panels with milled particles were 628.67 Kg / m3 ; water absorption 65.3% and 79.75% at 2 and 24 hours respectively, and swelling of 9.9% and 14.35% measured at 2 and 24 hours respectively. Regarding the characterization of mechanical properties of bending, the values recorded in samples prepared with fine particles of peanut husks resulted in MOR: 3.58 MPa, LOP 2.26 MPa and MOE 627 MPa. With respect to toughness, the highest value was observed in particle boards made from unmilled peanut husks: 1.58MPa. The characterized properties are still below the properties of commercial wood panels. Adjustments to the process of preparing the peanut husks plates will be incorporated in future experiencesFil: Granero, Ana Victoria. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Cordoba. Centro Experimental de la Vivienda Economica(i); ArgentinaFil: Gatani, Mariana Pilar. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Cordoba. Centro Experimental de la Vivienda Economica(i); ArgentinaFil: Medina, J. C. Universidad Nacional de Santiago del Estero. Facultad de Cs.forestales. Instituto de Tecnologia de la Madera; ArgentinaFil: Ruiz, A.. Universidad Nacional de Santiago del Estero. Facultad de Cs.forestales. Instituto de Tecnologia de la Madera; ArgentinaFil: Fiorelli, J.. Universidade de Sao Paulo; Brasil. Laboratorio de Construções e Ambiência. Faculdade de Zootecnia e Enghenaria de Alimentos; BrasilFil: Kreiker, Jeronimo Rafael. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Cordoba. Centro Experimental de la Vivienda Economica(i); ArgentinaFil: Lerda, Maria Josefina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Cordoba. Centro Experimental de la Vivienda Economica(i); Argentin
GogB Is an Anti-Inflammatory Effector that Limits Tissue Damage during Salmonella Infection through Interaction with Human FBXO22 and Skp1
Bacterial pathogens often manipulate host immune pathways to establish acute and chronic infection. Many Gram-negative bacteria do this by secreting effector proteins through a type III secretion system that alter the host response to the pathogen. In this study, we determined that the phage-encoded GogB effector protein in Salmonella targets the host SCF E3 type ubiquitin ligase through an interaction with Skp1 and the human F-box only 22 (FBXO22) protein. Domain mapping and functional knockdown studies indicated that GogB-containing bacteria inhibited IκB degradation and NFκB activation in macrophages, which required Skp1 and a eukaryotic-like F-box motif in the C-terminal domain of GogB. GogB-deficient Salmonella were unable to limit NFκB activation, which lead to increased proinflammatory responses in infected mice accompanied by extensive tissue damage and enhanced colonization in the gut during long-term chronic infections. We conclude that GogB is an anti-inflammatory effector that helps regulate inflammation-enhanced colonization by limiting tissue damage during infection
Complement component C4 structural variation and quantitative traits contribute to sex-biased vulnerability in systemic sclerosis
Altres ajuts: Fondo Europeo de Desarrollo Regional (FEDER), "A way of making Europe".Copy number (CN) polymorphisms of complement C4 play distinct roles in many conditions, including immune-mediated diseases. We investigated the association of C4 CN with systemic sclerosis (SSc) risk. Imputed total C4, C4A, C4B, and HERV-K CN were analyzed in 26,633 individuals and validated in an independent cohort. Our results showed that higher C4 CN confers protection to SSc, and deviations from CN parity of C4A and C4B augmented risk. The protection contributed per copy of C4A and C4B differed by sex. Stronger protection was afforded by C4A in men and by C4B in women. C4 CN correlated well with its gene expression and serum protein levels, and less C4 was detected for both in SSc patients. Conditioned analysis suggests that C4 genetics strongly contributes to the SSc association within the major histocompatibility complex locus and highlights classical alleles and amino acid variants of HLA-DRB1 and HLA-DPB1 as C4-independent signals
Multiple myeloma and SARS-CoV-2 infection: clinical characteristics and prognostic factors of inpatient mortality
There is limited information on the characteristics, prognostic factors, and outcomes of patients with multiple
myeloma (MM) hospitalized with COVID-19. This retrospective case series investigated 167 patients reported from 73
hospitals within the Spanish Myeloma Collaborative Group network in March and April, 2020. Outcomes were
compared with 167 randomly selected, contemporary, age-/sex-matched noncancer patients with COVID-19 admitted
at six participating hospitals. Among MM and noncancer patients, median age was 71 years, and 57% of patients were
male; 75 and 77% of patients, respectively, had at least one comorbidity. COVID-19 clinical severity was
moderate–severe in 77 and 89% of patients and critical in 8 and 4%, respectively. Supplemental oxygen was required
by 47 and 55% of MM and noncancer patients, respectively, and 21%/9% vs 8%/6% required noninvasive/invasive
ventilation. Inpatient mortality was 34 and 23% in MM and noncancer patients, respectively. Among MM patients,
inpatient mortality was 41% in males, 42% in patients aged >65 years, 49% in patients with active/progressive MM at
hospitalization, and 59% in patients with comorbid renal disease at hospitalization, which were independent
prognostic factors on adjusted multivariate analysis. This case series demonstrates the increased risk and identifies
predictors of inpatient mortality among MM patients hospitalized with COVID-19
CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative
Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
Plasma lipid profiles discriminate bacterial from viral infection in febrile children
Fever is the most common reason that children present to Emergency Departments. Clinical signs and symptoms suggestive of bacterial infection are often non-specific, and there is no definitive test for the accurate diagnosis of infection. The 'omics' approaches to identifying biomarkers from the host-response to bacterial infection are promising. In this study, lipidomic analysis was carried out with plasma samples obtained from febrile children with confirmed bacterial infection (n = 20) and confirmed viral infection (n = 20). We show for the first time that bacterial and viral infection produces distinct profile in the host lipidome. Some species of glycerophosphoinositol, sphingomyelin, lysophosphatidylcholine and cholesterol sulfate were higher in the confirmed virus infected group, while some species of fatty acids, glycerophosphocholine, glycerophosphoserine, lactosylceramide and bilirubin were lower in the confirmed virus infected group when compared with confirmed bacterial infected group. A combination of three lipids achieved an area under the receiver operating characteristic (ROC) curve of 0.911 (95% CI 0.81 to 0.98). This pilot study demonstrates the potential of metabolic biomarkers to assist clinicians in distinguishing bacterial from viral infection in febrile children, to facilitate effective clinical management and to the limit inappropriate use of antibiotics
Plan de emerxencias. Fundación Pública Urxencias Sanitarias de Galicia-061
A Fundación Pública Urxencias Sanitarias de Galicia-061 é a encargada de proporcionar, desde o momento que ocorre a emerxencia, un control da situación, unha primeira avaliación e unha asistencia sanitaria que logre salvar o maior número de vidas e volver á normalidade o antes posible. Para isto, a actuación sanitaria debe seguir unha metodoloxía perfectamente establecida, xa que as actuacións organizadas son as mellores ferramentas de traballo.
Así pois, é necesario posibilitar normas de actuación o máis protocolizadas posible, para poder traballar nas mellores condicións de seguridade e manter unhas directrices xerais, onde cada persoa coñeza tanto a súa función como a do resto dos componentes do equipo, procedendo, ademais, á súa identificación funcional mediante signos externos (uniformidade, carteis, identificación, etc.); para facilitar o entendemento e a coordinación de todos os implicados en resolver a situación acaecida.
Con este fin, preséntase o Plan de emerxencias que a continuación se expón, nun afán de dar sempre a mellor e máis axeitada resposta; obxectivo primordial desde que a FPUS de Galicia–061 se instaura como responsable da medicina prehospitalaria na nosa comunidade autónoma.La Fundación Pública Urxencias Sanitarias de Galicia-061 es la encargada de proporcionar, desde el momento en que ocurre la emergencia, un control de la situación, una primera evaluación y una asistencia sanitaria que logre salvar el mayor número de vidas y volver a la normalidad lo antes posible. Para esto, la actuación sanitaria debe seguir una metodología perfectamente establecida, ya que las actuaciones organizadas son las mejores herramientas de trabajo. Así pues, es necesario posibilitar normas de actuación lo más protocolizadas posible, para poder trabajar en las mejores condiciones de seguridad y mantener unas directrices generales, donde cada persona conozca tanto su función como la del resto de los componentes del equipo, procediendo, además, a su identificación funcional mediante signos externos (uniformidad, carteles, identificación, etc.); para facilitar el entendimiento y la coordinación de todos los implicados en resolver la situación acaecidad. Con este fin, se presenta el Plan de emergencias que a continuación se expone, en un afán de dar siempre la respuesta mejor y más idónea; objetivo primordial desde que la FPUS de Galicia-061 se instaura como responsable de la medicina prehospitalaria en nuestra comunidad autónoma
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